Buglyst Blog
Learn to debug under pressure.
Playbooks for fast pattern recognition, guides for the full investigation, and articles for the engineering judgment around the edges.
17 playbooks · 509 guides · 95 articles · 12 linked practice labs ·skip to practice
Fast pattern recognition for the production failures engineers see most often.
17 playbooks
Debugging Env Var Issues
A concise checklist for incidents where local works but CI, staging, or production changes behavior.
Debugging Cache Stampedes
How to recognize and contain request spikes when cached data expires.
Debugging CORS Origin Bugs
A practical way to inspect origin parsing, credentials, and header behavior.
Debugging Retry Bugs
Retry issues often hide the first failure and create duplicate work.
Debugging Timezone Bugs
Time bugs usually live at day boundaries, DST changes, and unit conversions.
Debugging Pagination Bugs
Pagination bugs hide in boundary math, cursor reuse, and new records arriving between pages.
Structured investigations for the failure modes engineers meet in real systems.
Debugging Node.js Cluster Module Worker Crashes
A hands-on guide to diagnosing and fixing worker crashes in Node.js cluster mode, covering uncaught exceptions, memory leaks, and IPC failures.
Debugging TypeScript Generic Type Constraint Errors
A practical guide to diagnosing and fixing TypeScript errors when generic type parameters violate their constraints, with real-world debugging strategies and a war story.
Mapped Types Returning 'never' or 'unknown' — What Your IDE Won't Tell You
A field guide for when mapped types silently collapse to 'never' or 'unknown', covering conditional checks, key remapping, and distributive conditional types.
JavaScript Closure Stale Variable Inside Loop
A debugging guide for the classic JavaScript closure-in-loop bug where callbacks capture the final value of a loop variable instead of each iteration's value.
TypeScript Discriminated Union Type Narrowing Not Working
A practical debugging guide for when TypeScript's discriminated union type narrowing fails due to common pitfalls like excess property checks, optional discriminants, and type assertions.
Debugging Prototype Chain Inheritance Bugs in JavaScript
A guide to diagnosing and fixing subtle bugs caused by shared state and unintended property shadowing in JavaScript prototype chains.
Long-form thinking on debugging habits, observability, and the systems around the bug.
The Debugging Mindset: A Systematic Method for Finding Root Causes
A repeatable, hypothesis-driven approach to debugging that works for intermittent failures, performance regressions, and production incidents.
Analyzing a Core Dump: What to Do When Your Process Goes Silent
A core dump is your process's last scream. Here's how to make it talk.
Timeouts Every Engineer Gets Wrong (and How to Fix Them)
Most timeout bugs aren't logic errors — they're configuration failures. Here's how to stop treating timeouts as magic numbers and start engineering them deliberately.
Backpressure in Streaming Systems: When Your Pipeline Fights Back
Backpressure is the system's way of saying 'slow down.' Ignore it and you get OOM crashes, silent data loss, or cascading failures. Here's how to design for it.
Finding Memory Leaks Step by Step: A Systematic Approach
Memory leaks are the silent killers of long-running services. Here's a repeatable process to hunt them down, from heap dumps to production monitoring.